The Earth comprises a biosphere in which micro-organisms, plants, and animals, including humans, exist in a more-or-less steady state. However, the amount of pollution introduced into the environment of the Earth is increasing, and the natural ability of the environment to dilute and detoxify this pollution is becoming overwhelmed. The pollution of the Earth's environment is leading to the extinction of many species of wildlife and may prove to threaten the survival of all life forms on Earth unless a means of detoxifying and recycling pollutants, created by man at an ever-increasing rate, is found and implemented.
Moreover, as man ventures beyond the bounds of Earth and into space or to the depths of the oceans, life support systems will necessarily have to be transported with him. The resources that go with man will be limited and not readily replaced. Therefore, it will be necessary to recycle these resources and to prevent an accumulation of pollutants generated within the closed environments.
It is desirable to provide a microcosm of Earth's environment, to study the interaction of components of the environment and a variety of forms of pollution that are generated on a daily basis, and to develop techniques for influencing our environment in a positive manner. Such studies are impossible, or difficult at best, in the open system provided on Earth, since matter is exchanged between the Earth's and the study's environments. This exchange results in a dilution of the pollutants that are generated by the study and, also, introduces extraneous pollutants from the surrounding atmosphere. To adequately test and evaluate the procedures for coping with the pollution generated by day-to-day life, it is desirable to provide a system that is completely enclosed. The enclosed environment prevents matter from being exchanged between the study and the Earth's environment. Since the environment is enclosed, and is of very limited volume, matter within the environment has to be recycled and detoxified, to prevent a rapid corruption of the air and water of the enclosed environment or the need to continually dedicate an ever-increasing portion of the enclosed environment to the storage of useless trash.
Currently, a completely contained ecological system, referred to as Biosphere 2, is being established near Oracle, Ariz. The system completely encloses about one hectare of land and about 175,000 cubic meters of space, isolated from the Earth's environment by an impermeable skin so that no matter is transferred.
Biosphere 2 is intended to be as complete a simulation of the Earth's environment as possible, and, therefore, the diversity of the micro-environments that exist on Earth are duplicated within Biosphere 2. As a result of this diversity of micro-environments, a suitable ecosystem for the growth of the numerous organisms selected from these micro-environments, including man, is also provided.
An essential component of the environment of Earth and, therefore, Biosphere 2 is water. Water acts as a means of transporting pollutants or nutrients away from a region where they are created, diluting them, and carrying them to other regions, where they can be detoxified or used as sustenance for other organisms. The aqueous components of Biosphere 2 consists of saltwater, freshwater, and potable water. Each of these water systems provides a suitable micro-environment for the establishment of a variety of organisms, including man. Nutrients/pollutants that accumulate in one micro-environment, by the actions of the organisms present in that micro-environment, can be transported to another micro-environment, where they are removed by the different organisms that are present.
As well as distribution of nutrients and dilution of pollutants, water circulation is necessary to aerate the water and prevent stagnation. This water circulation therefore provides the general conditions suitable to foster the growth of a wide variety of diverse organisms.
Water within Biosphere 2 is limited and, therefore, must be recycled. It is important that water be appropriately treated, decontaminated, or purified at each step within the complete water cycle. For example, saltwater must be desalted before it is introduced into a freshwater micro-environment, and waste water and sewage must be purified and decontaminated before the water can be reused, thus preventing the possible accumulation and spread of pathogenic organisms.
The treatment, decontamination, and purification of water in this closed environment, therefore, provide a model for water purification and recycling in the environment of Earth and for the establishment of extraterrestrial or undersea colonies or other closed systems.
The operation of Biosphere 2 demonstrates the feasibility and efficiency of such methodologies.